Assembly of Internal Components

Replace all O-rings, rubber seals and gaskets with new parts. Place the rotor on a rubber pad or cloth. Coat all the engine sliding surfaces with clean engine oil.

Install the oil seal rings in their respective grooves in the rotors with the edge of the spring in the stopper hole. The oil seal springs are painted cream or blue in color. The cream colored springs must be installed on the front faces of both rotors. The blue colored springs must be installed on the rear faces of both rotors. When installing each oil seal spring, the painted, square side of the spring must face upward toward the oil seal.

Fig. Fig. 1: Oil seal spring installation

Fig. Fig. 2: A used inner oil seal makes a good installation tool for pressing in the new seal

Coat the new O-ring with clean engine oil and install in each seal groove. Place each oil seal in the groove so that the square edge of the spring fits in the stopper hole of the oil seal. Push on the head of the oil seal slowly with your fingers, being careful that the seal is not deformed. Be sure that the oil seal moves smoothly in the groove before installing the O-ring. An old seal can be used as an installation tool.

Lubricate each oil seal and groove with engine oil. Check the movement of the seal. It should move freely when the head of the seal is pressed.

Check the oil seal protrusion and install the seals on the other side of each rotor. Oil seal protrusion must not exceed 0.016 in. (0.4mm).

Install the apex seals (without springs and side pieces) into their respective grooves, so that each side piece will be positioned to the rear side of the rotor.

Install the corner seal springs and corner seals into their respective grooves.

Install the side seal springs and side seals into their respective grooves.

Confirm the smooth movement of each seal by pressing its head.

Fig. Fig. 3: When meshing the internal and stationary gears, make sure at least one of the rotor apexes is positioned as shown

Fig. Fig. 4: Apply sealant to the front side of the front rotor housing

Mount the front housing on a workstand so that the top of the housing is up. Install the thrust plate so that the chamfered edge faces the front of the housing. Torque the thrust plate bolts to 12-17 ft. lbs. (16-23 Nm).

Lubricate the internal gear of the rotor with engine oil.

Hold the apex seals with a rubber band around the rotor's perimeter to keep the seals attached. Place the rotor on the front housing, being careful not to drop the seals. Turn the front housing so that the sliding surface faces upward.

Mesh the internal and stationary gears so that one of the rotor apexes is at any one of the four places shown, then remove the rubber band which is holding the apex seals in position.

Lubricate the front rotor journal of the eccentric shaft and the eccentric shaft main journal with engine oil.

Insert the eccentric shaft. Be careful that you do not damage the rotor bearing and main bearing.

Apply sealing agent to the front side of the front rotor housing.

Apply a light coat of petroleum jelly (not grease) onto new O-rings and rubber seals, then install the O-rings and seals on the front side of the rotor housing. If the engine is being overhauled, install the seal protector behind the inner sealing rubber to improve durability.

The inner rubber seal is of the square type. The wider white line of the rubber seal should face the combustion chamber and the seam of the rubber seal should be positioned as illustrated. Do not stretch the rubber seal.

Fig. Fig. 7: Fitting an assist piece on the apex seal

Fig. Fig. 8: Install the side piece as shown under "O." (The spring must butt against the apex seal lip.)

Fig. Fig. 9: Rotary engine tension bolt tightening sequence

Invert the front rotor housing, being careful not to let the rubber seals and O-rings fall from their grooves, and mount it on the front housing.

Lubricate the tubular dowels with engine oil, then insert them through the front rotor housing holes and into the front housing.

Insert each apex seal spring so that both ends of the spring may support the back side of the seal.

Install the corner seal springs and corner seals into their respective grooves.

Install the side seal springs and side seals into their respective grooves.

Fit an assist piece between the spring and seal, then install each side piece in its original position. Be sure that the spring seats properly on the side piece, as shown.

Confirm the smooth movement of each seal by pressing its head.

Apply sealer to the rear side of the front rotor housing.

Install new O-rings, rubber seals and seal protector on the rear side of the front rotor housing, in the same manner as on the front side.

Lubricate the side pieces with engine oil. Make sure that the front rotor housing is free of foreign matter and lubricate the sliding surface of the front housing with engine oil.

Turn the front housing assembly with the rotor, so that the top of the housing is up. Pull the eccentric shaft about 1 in. (25mm).

Position the eccentric portion of the eccentric shaft diagonally, to the upper right.

Install the intermediate housing over the eccentric shaft and onto the front rotor housing. Turn the engine so that the rear of the engine is up.

Install the rear rotor and rear rotor housing, following the same steps as for the front rotor and front rotor housing.

Lubricate the stationary gear and main bearing.

Install the rear housing onto the rear rotor housing. Make sure the side pieces of the front and rear apex seals are not pinched between the rotor and side housings.

If necessary, turn the rear rotor slightly to mesh the rear housing stationary gear with the rear rotor internal gear.

Install a new washer on each tension bolt, and lubricate each bolt with engine oil.

Install the tension bolts, then tighten them to specification using several stages of the proper sequence. Be sure the bolts are installed in their original positions with new seal washers. Longer bolts are used in later engines and are not interchangeable.

On 1984-85 carbureted engines, bolt number 11 does not apply. For those engines, delete bolt number 11 from the tension bolt torque sequence.

After tightening the bolts, turn the eccentric shaft to be sure that the shaft and rotors turn smoothly and easily.

Lubricate the oil seal in the rear housing.

On vehicles equipped with a manual transmission, install the flywheel on the rear of the eccentric shaft so that the keyway of the flywheel fits the key on the shaft.

Apply sealer to both sides of the flywheel lockwasher and install the lockwasher.

On vehicles with an automatic transmission, install the key, counterweight, lockwasher and nut. Tighten the nut to 350 ft. lbs. (475 Nm). Install the driveplate on the counterweight and tighten the attaching nuts.

Turn the engine so that the front faces up.

Install the thrust plate with the tapered face down, and install the needle bearing on the eccentric shaft. Lubricate with engine oil.

Install the bearing housing on the front housing. Tighten the bolts and bend up the lockwasher tabs. The spacer should be installed so that the center of the needle bearing comes to the center of the eccentric shaft, and the spacer should be seated on the thrust plate.

Install the needle bearing on the shaft and lubricate it with engine oil.

Install the balancer and thrust washer on the eccentric shaft.

Install the oil pump drive chain over both of the sprockets. Install the sprocket and chain assembly over the eccentric shaft and oil pump shaft simultaneously. Install the key on the eccentric shaft. Be sure that both of the sprockets are engaged with the chain before installing them over the shafts.

Install the distributor drive gear onto the eccentric shaft with the
F
mark on the gear facing the front of the engine. Slide the spacer and oil slinger onto the eccentric shaft.

Attach a dial indicator to the flywheel. Move the flywheel forward and backward.

Note the reading on the dial indicator, it should be 0.0016-0.0028 in. (0.04-0.07mm).

If the end-play is not within specification, adjust it by replacing the front spacer. Spacers come in four sizes, ranging from 0.3150-0.3181 in. (8.00-8.08mm). If necessary, a spacer can be ground on a surface plate with emery paper.

Check the end-play again and, if it is now within specification, proceed with the next Step.

Remove the pulley from the front of the eccentric shaft. Tighten the oil pump drive sprocket nut and bend the locktabs on the lockwasher.

Fit a new O-ring over the front cover oil passage.

Install the chain tensioner, if equipped, and tighten its securing bolts.

Position the front cover gasket and the front cover on the front housing, then secure the front cover with its attachment bolts.